In the branch of linguistics known as pragmatics, a presupposition (or PSP) is an implicit assumption
about the world or background belief relating to an utterance whose truth is taken for granted
in discourse. Examples of presuppositions include:
Jane no longer writes fiction. Presupposition: Jane once wrote fiction.
Have you stopped eating meat? Presupposition: you had once eaten meat.
Have you talked to Hans? Presupposition: Hans exists.A presupposition
must be mutually known or assumed by the speaker and addressee for the utterance to be considered
appropriate in context. It will generally remain a necessary assumption whether the
utterance is placed in the form of an assertion, denial, or question, and can be associated
with a specific lexical item or grammatical feature (presupposition trigger) in the utterance.
Crucially, negation of an expression does not change its presuppositions: I want to
do it again and I don't want to do it again both presuppose that the subject has done
it already one or more times; My wife is pregnant and My wife is not pregnant both presuppose
that the subject has a wife. In this respect, presupposition is distinguished from entailment
and implicature. For example, The president was assassinated entails that The president
is dead, but if the expression is negated, the entailment is not necessarily true.
== Negation of a sentence containing a presupposition ==
If presuppositions of a sentence are not consistent with the actual state of affairs, then one
of two approaches can be taken. Given the sentences My wife is pregnant and My wife
is not pregnant when one has no wife, then either:
Both the sentence and its negation are false; or
Strawson's approach: Both "my wife is pregnant" and "my wife is not pregnant" use a wrong
presupposition (i.e. that there exists a referent which can be described with the noun phrase
my wife) and therefore can not be assigned truth values.Bertrand Russell tries to solve
this dilemma with two interpretations of the negated sentence:
"There exists exactly one person, who is my wife and who is not pregnant"
"There does not exist exactly one person, who is my wife and who is pregnant."For the
first phrase, Russell would claim that it is false, whereas the second would be true
according to him.
== Projection of presuppositions == A presupposition of a part of an utterance
is sometimes also a presupposition of the whole utterance, and sometimes not. For instance,
the phrase my wife triggers the presupposition that I have a wife. The first sentence below
carries that presupposition, even though the phrase occurs inside an embedded clause. In
the second sentence, however, it does not. John might be mistaken about his belief that
I have a wife, or he might be deliberately trying to misinform his audience, and this
has an effect on the meaning of the second sentence, but, perhaps surprisingly, not on
the first one.
John thinks that my wife is beautiful. John said that my wife is beautiful.Thus,
this seems to be a property of the main verbs of the sentences, think and say, respectively.
After work by Lauri Karttunen, verbs that allow presuppositions to "pass up" to the
whole sentence ("project") are called holes, and verbs that block such passing up, or projection
of presuppositions are called plugs. Some linguistic environments are intermediate between
plugs and holes: They block some presuppositions and allow others to project. These are called
filters. An example of such an environment are indicative conditionals ("If-then" clauses).
A conditional sentence contains an antecedent and a consequent. The antecedent is the part
preceded by the word "if," and the consequent is the part that is (or could be) preceded
by "then." If the consequent contains a presupposition trigger, and the triggered presupposition
is explicitly stated in the antecedent of the conditional, then the presupposition is
blocked. Otherwise, it is allowed to project up to the entire conditional. Here is an example:
If I have a wife, then my wife is blonde.Here, the presupposition triggered by the expression
my wife (that I have a wife) is blocked, because it is stated in the antecedent of the conditional:
That sentence doesn't imply that I have a wife. In the following example, it is not
stated in the antecedent, so it is allowed to project, i.e. the sentence does imply that
I have a wife.
If it's already 4am, then my wife is probably angry.Hence, conditional sentences act as
filters for presuppositions that are triggered by expressions in their consequent.
A significant amount of current work in semantics and pragmatics is devoted to a proper understanding
of when and how presuppositions project.
== Presupposition triggers == A presupposition trigger is a lexical item
or linguistic construction which is responsible for the presupposition. The following is a
selection of presuppositional triggers following Stephen C. Levinson's classic textbook on
Pragmatics, which in turn draws on a list produced by Lauri Karttunen. As is customary,
the presuppositional triggers themselves are italicized, and the symbol » stands for 'presupposes'.
=== Definite descriptions ===
Definite descriptions are phrases of the form "the X" where X is a noun phrase. The description
is said to be proper when the phrase applies to exactly one object, and conversely, it
is said to be improper when either there exist more than one potential referents, as in "the
senator from Ohio", or none at all, as in "the king of France". In conventional speech,
definite descriptions are implicitly assumed to be proper, hence such phrases trigger the
presupposition that the referent is unique and existent.
John saw the man with two heads. »there exists a man with two heads.
=== Factive verbs ===
In Western epistemology, there is a tradition originating with Plato of defining knowledge
as justified true belief. On this definition, for someone to know X, it is required that
X be true. A linguistic question thus arises regarding the usage of such phrases: does
a person who states "John knows X" implicitly claim the truth of X? Steven Pinker explored
this question in a popular science format in a 2007 book on language and cognition,
using a widely publicized example from a speech by a U.S. president. A 2003 speech by George
W. Bush included the line, "British Intelligence has learned that Saddam Hussein recently sought
significant quantities of uranium from Africa." Over the next few years, it became apparent
that this intelligence lead was incorrect. But the way the speech was phrased, using
a factive verb, implicitly framed the lead as truth rather than hypothesis. There is
however a strong alternative view that factivity thesis, the proposition that relational predicates
having to do with knowledge, such as knows, learn, remembers, and realized, presuppose
the factual truth of their object, is incorrect. Martha regrets drinking John's home brew.
Presupposition: Martha did in fact drink John's home brew.
Frankenstein was aware that Dracula was there. Presupposition: Dracula was in fact there.
John realized that he was in debt. Presupposition: John was in fact in debt.
It was odd how proud he was. Presupposition: He was in fact proud.Some
further factive predicates: know; be sorry that; be proud that; be indifferent that;
be glad that; be sad that.
=== Implicative verbs === John managed to open the door.»John tried
to open the door. John forgot to lock the door.»John ought
to have locked, or intended to lock, the door.Some further implicative predicates: X happened
to V»X didn't plan or intend to V; X avoided Ving»X was expected to, or usually did, or
ought to V, etc.
=== Change of state verbs === John stopped teasing his wife.»John had been
teasing his wife. Joan began teasing her husband.»Joan hadn't
been teasing her husband.Some further change of state verbs: start; finish; carry on; cease;
take (as in X took Y from Z » Y was at/in/with Z); leave; enter; come; go; arrive; etc.
=== Iteratives === The flying saucer came again.»The flying
saucer came before. You can't get gobstoppers anymore.»You once
could get gobstoppers. Carter returned to power.»Carter held power
before.Further iteratives: another time; to come back; restore; repeat; for the nth time.
=== Temporal clauses === Before Strawson was even born, Frege noticed
presuppositions.»Strawson was born. While Chomsky was revolutionizing linguistics,
the rest of social science was asleep.»Chomsky was revolutionizing linguistics.
Since Churchill died, we've lacked a leader.»Churchill died.Further temporal clause constructors:
after; during; whenever; as (as in As John was getting up, he slipped).
=== Cleft sentences === Cleft construction: It was Henry that kissed
Rosie.»Someone kissed Rosie. Pseudo-cleft construction: What John lost
was his wallet.»John lost something.
=== Comparisons and contrasts === Comparisons and contrasts may be marked by
stress (or by other prosodic means), by particles like "too", or by comparatives constructions.
Marianne called Adolph a male chauvinist, and then HE insulted HER.»For Marianne to
call Adolph a male chauvinist would be to insult him.
Carol is a better linguist than Barbara.»Barbara is a linguist.
=== Counterfactual conditionals === If the notice had only said 'mine-field' in
Welsh as well as in English, we would never have lost poor Llewellyn.»The notice didn't
say 'mine-field' in Welsh.
=== Questions === Questions often presuppose what the assertive
part of the question presupposes, but interrogative parts might introduce further presuppositions.
There are three different types of questions: yes/no questions, alternative questions and
WH-questions.
Is there a professor of linguistics at MIT?»Either there is a professor of linguistics at MIT
or there isn't. Is Newcastle in England or in Australia?»Newcastle
is in England or Newcastle is in Australia. Who is the professor of linguistics at MIT?»Someone
is the professor of linguistics at MIT.
=== Possessive case === John's children are very noisy.»John has
children.
== Accommodation of presuppositions == A presupposition of a sentence must normally
be part of the common ground of the utterance context (the shared knowledge of the interlocutors)
in order for the sentence to be felicitous. Sometimes, however, sentences may carry presuppositions
that are not part of the common ground and nevertheless be felicitous. For example, I
can, upon being introduced to someone, out of the blue explain that my wife is a dentist,
this without my addressee having ever heard, or having any reason to believe that I have
a wife. In order to be able to interpret my utterance, the addressee must assume that
I have a wife. This process of an addressee assuming that a presupposition is true, even
in the absence of explicit information that it is, is usually called presupposition accommodation.
We have just seen that presupposition triggers like my wife (definite descriptions) allow
for such accommodation. In "Presupposition and Anaphora: Remarks on the Formulation of
the Projection Problem", the philosopher Saul Kripke noted that some presupposition triggers
do not seem to permit such accommodation. An example of that is the presupposition trigger
too. This word triggers the presupposition that, roughly, something parallel to what
is stated has happened. For example, if pronounced with emphasis on John, the following sentence
triggers the presupposition that somebody other than John had dinner in New York last
night.
John had dinner in New York last night, too.But that presupposition, as stated, is completely
trivial, given what we know about New York. Several million people had dinner in New York
last night, and that in itself doesn't satisfy the presupposition of the sentence. What is
needed for the sentence to be felicitous is really that somebody relevant to the interlocutors
had dinner in New York last night, and that this has been mentioned in the previous discourse,
or that this information can be recovered from it. Presupposition triggers that disallow
accommodation are called anaphoric presupposition triggers.
== Presupposition in critical discourse analysis ==
Critical discourse analysis (CDA) seeks to identify presuppositions of an ideological
nature. CDA is critical, not only in the sense of being analytical, but also in the ideological
sense.Van Dijk (2003) says CDA "primarily studies the way social power abuse, dominance,
and inequality" operate in speech acts (including written text)—"text and talk". Van Dijk
describes CDA as written from a particular point of view: "dissendent research" aimed
to "expose" and "resist social inequality." One notable feature of ideological presuppositions
researched in CDA is a concept termed synthetic personalisation.
== See also == Fallacy of many questions
Loaded question Performative contradiction
Exception that proves the rule Assumption/presumption (similar words)Fallacies:Double-barreled
question Self-refuting idea